Reinforcement of elastomers is usually accomplished by the addition of carbon black or short fibers. Such reinforcement is disclosed, for example in L. A. Goettler, et al., Rubber Chem. Technol., vol. 56, pg. 619 (1983) and in S. R. Moghe, Rubber World, pg. 16 (February, 1983). However, it is difficult to achieve uniform dispersion, especially in the case of short fiber reinforcement. In addition, during processing, entanglement or breakage of fibers may occur. In recent years, a series of elastomers reinforced by cellulosic fibers with improved properties has been developed. Their preparation is based on the mixing of melt spun fibers with thermoplastic elastomers.
Liquid crystalline polymers (LCP's) have been mentioned as a possible reinforcement for thermoplastic materials for improvement of their mechanical properties. These so-called self-reinforced composites usually consist of LCP's based on aromatic copolyesters having high melting temperatures. U.S. Pat. No. 4,728,698 to Isayev (the inventor herein) et al. discloses such self-reinforced composites.